Kev hloov pauv tib neeg yog qhov hloov pauv uas tshwm sim hauv lub cell ntawm qib DNA. Lawv tuaj yeem ua tau ntau hom. Tib neeg kev hloov pauv tuaj yeem ua rau nruab nrab. Hauv qhov no, ib qho kev hloov pauv ntawm nucleoids tshwm sim. Cov kev hloov pauv tuaj yeem tsim teeb meem. Lawv yog cov yam ntxwv los ntawm kev mob siab rau phenotypic nyhuv. Kev hloov pauv ntawm tib neeg kuj tuaj yeem muaj txiaj ntsig zoo. Hauv qhov no, cov kev hloov pauv muaj cov nyhuv phenotypic me ntsis. Tom ntej no, cia peb saib ze dua seb tus neeg hloov pauv li cas. Cov piv txwv ntawm cov kev hloov pauv tseem yuav muab rau hauv kab lus.
Kev faib tawm
Muaj ntau hom kev hloov pauv. Ib txhia ntawm cov qeb muaj, nyob rau hauv lem, lawv tus kheej classification. Tshwj xeeb, muaj cov kev hloov pauv hauv qab no:
- Somatic.
- YChromosomal.
- Cytoplasmic.
- Genomic mutations hauv tib neeg thiab lwm tus.
Kev hloov pauv tshwm sim nyob rau hauv kev cuam tshuam ntawm ntau yam. Chernobyl yog suav hais tias yog ib qho ntawm cov teeb meem zoo tshaj plaws ntawm kev tshwm sim ntawm cov kev hloov pauv no. Kev hloov pauv ntawm tib neeg tom qab kev puas tsuaj tsis tshwm sim tam sim ntawd. Txawm li cas los xij, dhau sijhawm lawv tau hais ntau dua.
Human Chromosomal Mutations
Cov kev hloov no yog cov yam ntxwv ntawm kev cuam tshuam ntawm cov qauv. Kev tawg tshwm sim hauv chromosomes. Lawv nrog txawvrestructuring nyob rau hauv cov qauv. Vim li cas tib neeg kev hloov pauv tshwm sim? Cov laj thawj yog lwm yam:
- Lub cev. Cov no suav nrog gamma thiab x-rays, raug ultraviolet, kub (siab / qis), electromagnetic teb, siab, thiab ntau dua.
- Tshuaj. Cov pawg no suav nrog cawv, cytostatics, ntsev ntawm cov hlau hnyav, phenols thiab lwm yam sib xyaw.
- Biological. Cov no suav nrog cov kab mob thiab kab mob.
Kev hloov kho tus kheej
Kev hloov pauv ntawm tib neeg hauv qhov xwm txheej no tshwm sim nyob rau hauv ib txwm muaj. Txawm li cas los xij, xws li kev hloov pauv hauv cov xwm txheej no tsis tshua muaj: rau 1 lab luam ntawm ib qho gene, 1-100 kis. Tus kws tshawb fawb Haldane tau xam qhov nruab nrab qhov tshwm sim ntawm qhov tshwm sim ntawm qhov tshwm sim. Nws muaj 510-5 rau ib tiam. Txoj kev loj hlob ntawm tus txheej txheem spontaneous nyob ntawm sab nraud thiab sab hauv - kev hloov pauv siab ntawm ib puag ncig.
yam ntxwv
Chromosomal mutations feem ntau yog muab faib ua teeb meem. Pathologies uas tsim los ntawm kev hloov kho tshiab feem ntau tsis sib haum nrog lub neej. Lub ntsiab yam ntxwv ntawm chromosomal mutations yog qhov randomness ntawm rearrangement. Vim yog lawv, ntau haiv neeg tshiab "coalitions" raug tsim. Cov kev hloov pauv no hloov kho cov kev ua haujlwm ntawm cov noob, faib cov ntsiab lus random thoob plaws hauv genome. Lawv qhov kev hloov pauv tus nqi yog txiav txim los ntawm tus txheej txheem xaiv.
Chromosomal mutations: kev faib tawm
Muaj peb txoj hauv kev rau kev hloov pauv. Tshwj xeeb, muaj iso-, inter- thiabintrachromosomal kev hloov pauv. Cov tom kawg yog tus cwj pwm los ntawm kev sib txawv ntawm cov qauv (aberations). Lawv pom nyob rau hauv tib chromosome. Cov kev hloov pauv no suav nrog:
- Kev tshem tawm. Cov kev hloov pauv no sawv cev rau qhov poob ntawm ib feem sab hauv lossis qhov kawg ntawm chromosome. Kev hloov kho ntawm hom no tuaj yeem ua rau muaj ntau yam tsis txaus ntseeg thaum lub sij hawm embryonic txoj kev loj hlob (piv txwv li, lub plawv tsis xws luag).
- Inversions. Qhov kev hloov pauv no suav nrog kev sib hloov ntawm cov chromosome feem ntawm 180 degrees. thiab muab tso rau hauv nws qhov chaw qub. Nyob rau tib lub sijhawm, qhov kev txiav txim ntawm kev teeb tsa ntawm cov qauv tsim tau ua txhaum, tab sis qhov no tsis cuam tshuam rau phenotype yog tias tsis muaj lwm yam ntxiv.
- Dua. Lawv sawv cev qhov sib npaug ntawm ib feem ntawm chromosome. Xws li kev sib txawv ntawm tus qauv provokes human hereditary mutations.
Interchromosomal rearrangements (translocations) yog kev sib pauv chaw ntawm cov ntsiab lus uas muaj cov noob zoo sib xws. Cov kev hloov no tau muab faib ua:
- Robertsonian. Ib tug metacentric chromosome yog tsim los ntawm ob tug acrocentric chromosomes.
- Tsis sib xws. Hauv qhov no, ib feem ntawm ib chromosome txav mus rau lwm qhov.
- Kev sib tw. Nrog xws li rearrangements, muaj kev sib pauv ntawm ob lub ntsiab.
Isochromosomal mutations tshwm sim los ntawm kev tsim cov ntawv luam ntawm chromosome, daim iav seem ntawm ob, uas muaj tib cov noob caj noob ces. Xws li kev sib txawv ntawm cov qauv yog hu ua kev sib txuas centric vim qhov tseebtransverse sib cais ntawm chromatids, uas tshwm sim los ntawm centromeres.
Type of change
Muaj cov qauv thiab cov lej chromosomal hloov pauv. Cov tom kawg, nyob rau hauv lem, muab faib ua aneuploidy (qhov no yog qhov tsos (trisomy) los yog poob (monosomy) ntawm cov ntsiab lus ntxiv) thiab polyploidy (qhov no yog ntau qhov nce hauv lawv tus lej).
Cov qauv kev hloov kho yog sawv cev los ntawm kev hloov pauv, tshem tawm, hloov chaw, ntxig, centric rings thiab isochromosomes.
Kev sib tham ntawm ntau yam kev hloov kho
Genomic mutations yog qhov txawv los ntawm kev hloov pauv ntawm cov qauv tsim. Gene mutations yog kev cuam tshuam hauv cov qauv ntawm cov noob. Chromosomal mutations cuam tshuam cov qauv ntawm chromosomes lawv tus kheej. Thawj thiab zaum kawg, nyob rau hauv lem, muaj tib yam kev faib tawm rau polyploidy thiab aneuploidy. Kev hloov pauv hloov pauv ntawm lawv yog Robertsonian hloov chaw. Cov kev hloov pauv no tau koom ua ke los ntawm cov kev taw qhia thiab lub tswv yim hauv tshuaj xws li "chromosomal abnormalities". Nws suav nrog:
- Somatic pathologies. Cov no suav nrog hluav taws xob pathology, piv txwv li.
- Cov kab mob hauv lub cev. Nws tuaj yeem yog rho menyuam tawm, nchuav menyuam.
- kab mob chromosomal. Cov no suav nrog Down syndrome thiab lwm yam.
Txog hnub no, paub txog ib puas qhov tsis txaus ntseeg. Tag nrho cov ntawm lawv tau tshawb fawb thiab piav qhia. Kwv yees li 300 daim ntawv tau nthuav tawm ua tus mob.
Ntseeg ntawm congenital pathologies
Hereditary mutations yog qhov dav heev. Pawg nocharacterized los ntawm ntau yam kev loj hlob tsis xws luag. Kev ua txhaum cai yog tsim los ntawm kev hloov pauv loj tshaj plaws hauv DNA. Kev puas tsuaj tshwm sim thaum lub sij hawm fertilization, maturation ntawm gametes, nyob rau hauv thawj theem ntawm qe faib. Kev ua tsis tiav tuaj yeem tshwm sim thaum cov niam txiv noj qab haus huv zoo tag nrho. Cov txheej txheem niaj hnub no tseem tsis tau tswj hwm thiab tsis tau kawm tiav.
Qhov tshwm sim ntawm kev hloov
Cov teeb meem ntawm kev hloov pauv ntawm chromosomal feem ntau tsis zoo rau tib neeg. Lawv feem ntau provoke:
- 70% spontaneous rho menyuam.
- Txhob Cia Siab.
- At 7.2% - tseem yug menyuam.
- Tumor formation.
Tawm tsam keeb kwm ntawm chromosomal pathologies, theem ntawm kev puas tsuaj hauv lub cev yog txiav txim siab los ntawm ntau yam: hom anomaly, ntau dhau lossis tsis txaus cov khoom hauv ib tus neeg chromosome, ib puag ncig, genotype ntawm kab mob.
Pathology pawg
Txhua tus kab mob chromosomal muab faib ua ob pawg. Thawj suav nrog cov provoked los ntawm kev ua txhaum cai ntawm cov ntsiab lus. Cov kab mob no ua rau feem ntau ntawm cov kab mob chromosomal. Ntxiv rau trisomy, monosomy thiab lwm hom polysomy, pab pawg no suav nrog tetraploidy thiab triploidy (nyob rau hauv qhov kev tuag tshwm sim hauv plab lossis thawj ob peb teev tom qab yug me nyuam). Down syndrome yog feem ntau tshwm sim. Nws yog nyob ntawm qhov tsis xws ntawm caj ces. Down's disease muaj npe tom qab tus kws kho menyuam yaus uas tau piav qhia hauv xyoo 1886. Niaj hnub no, tus mob no yog suav tias yog qhov kev tshawb fawb tshaj plaws ntawm tag nrho cov chromosomal txawv txav. Pathology tshwm sim hauv ib kis ntawm 700. Cov pab pawg thib ob suav nrog cov kab mob tshwm sim los ntawm kev hloov pauv hauv cov chromosomes. Cov cim qhia ntawm cov kab mob no suav nrog:
- Stunting.
- Mental retardation.
- Ntxhais qhov muag.
- Heart defects (congenital) thiab lwm yam.
Qee cov kab mob tshwm sim los ntawm kev hloov pauv ntawm cov chromosomes kev sib deev. Cov neeg mob nrog cov kev hloov pauv no tsis muaj cov xeeb ntxwv. Txog rau tam sim no, tsis muaj kev kho kom meej etiological ntawm cov kab mob zoo li no. Txawm li cas los xij, cov kab mob tuaj yeem tiv thaiv los ntawm kev kuaj mob ua ntej yug menyuam.
Role in evolution
Tawm tsam keeb kwm yav dhau los ntawm kev hloov pauv hauv cov xwm txheej, kev hloov pauv uas yav dhau los ua teeb meem tuaj yeem ua tau txiaj ntsig. Yog li ntawd, xws li rearrangements yog suav tias yog cov khoom rau xaiv. Yog tias qhov kev hloov pauv tsis cuam tshuam rau "tseem ceeb" DNA tawg lossis nws ua rau muaj kev hloov pauv ntawm ib qho kev sib txuas nrog ib qho kev sib txuas, ces, raws li txoj cai, nws tsis tshwm sim nws tus kheej hauv txhua txoj hauv kev hauv phenotype. Txawm li cas los xij, xws li kev kho dua tshiab tuaj yeem pom. Rau qhov no, txoj kev tshuaj ntsuam genetic tsom xam yog siv. Vim lub fact tias cov kev hloov pauv tshwm sim los ntawm kev cuam tshuam ntawm tej yam ntuj tso, yog li ntawd, piv txwv li, cov yam ntxwv tseem ceeb ntawm lub sab nrauv ib puag ncig nyob twj ywm unchanged, nws hloov tawm hais tias kev hloov pauv tshwm sim nyob rau hauv ib tug kwv yees li qhov zaus. Qhov tseeb no tuaj yeem siv rau hauv kev kawm ntawm phylogeny - kev tsom xam ntawm tsev neeg kev sib raug zoo thiab keeb kwm ntawm kev sib txawv taxa, suav nrog tib neeg. Hauv kev sib txuas nrogYog li kev hloov kho tshiab hauv "cov noob uas ntsiag to" ua raws li "lub moos molecular" rau cov kws tshawb fawb. Txoj kev xav kuj xav tias feem ntau ntawm cov kev hloov pauv tsis yog nruab nrab. Lawv tus nqi ntawm tsub zuj zuj nyob rau hauv ib tug tshwj xeeb gene yog qaug zog los yog kiag li ywj siab ntawm lub ntuj xaiv. Raws li qhov tshwm sim, qhov kev hloov pauv hloov mus tas li nyob rau lub sijhawm ntev. Txawm li cas los xij, cov noob sib txawv yuav muaj qhov sib txawv.
Nyob hauv kaw
Kawm txog cov txheej txheem ntawm qhov tshwm sim, kev txhim kho ntxiv ntawm kev hloov pauv hauv mitochondrial deoxyribonucleic acid, uas dhau mus rau cov xeeb ntxwv los ntawm leej niam kab, thiab hauv Y-chromosomes kis los ntawm leej txiv, yog dav siv niaj hnub no hauv evolutionary biology. Cov ntaub ntawv khaws tseg, txheeb xyuas thiab ua kom zoo, cov txiaj ntsig kev tshawb fawb tau siv rau hauv kev tshawb fawb txog keeb kwm ntawm ntau haiv neeg thiab haiv neeg. Cov ntaub ntawv tseem ceeb tshwj xeeb hauv kev taw qhia ntawm kev rov tsim kho ntawm kev tsim thiab kev loj hlob ntawm noob neej.
